Parser: capture named fields block separators

docs/release-notes/.FSharp.Compiler.Service/10.0.100.md

@@ -26,6 +26,7 @@
 
 ### Changed
 * Use `errorR` instead of `error` in `CheckDeclarations.fs` when possible. ([PR #18645](https://github.com/dotnet/fsharp/pull/18645))
+* Parser: Capture named fields block separators. ([PR #18857](https://github.com/dotnet/fsharp/pull/18857))
 * Type checker: use inner expr range in upcast constraints errors ([PR #18850](https://github.com/dotnet/fsharp/pull/18850))
 
 ### Breaking Changes

src/Compiler/Checking/CheckPatterns.fs

@@ -457,7 +457,13 @@ and TcPatArrayOrList warnOnUpper cenv env vFlags patEnv ty isArray args m =
     phase2, acc
 
 and TcRecordPat warnOnUpper (cenv: cenv) env vFlags patEnv ty fieldPats m =
-    let fieldPats = fieldPats |> List.map (fun (fieldId, _, fieldPat) -> fieldId, fieldPat)
+    let fieldPats = 
+        fieldPats 
+        |> List.map (fun (NamePatPairField(fieldName = fieldLid; pat = pat)) -> 
+            match fieldLid.LongIdent with
+            | [id] -> ([], id), pat
+            | lid -> List.frontAndBack lid, pat)
+
     match BuildFieldMap cenv env false ty fieldPats m with
     | None -> (fun _ -> TPat_error m), patEnv
     | Some(tinst, tcref, fldsmap, _fldsList) ->
@@ -503,7 +509,9 @@ and CheckNoArgsForLiteral args m =
 and GetSynArgPatterns args =
     match args with
     | SynArgPats.Pats args -> args
-    | SynArgPats.NamePatPairs (pats = pairs) -> List.map (fun (_, _, pat) -> pat) pairs
+    | SynArgPats.NamePatPairs (pats = pairs) ->
+        pairs
+        |> List.map _.Pattern
 
 and TcArgPats warnOnUpper (cenv: cenv) env vFlags patEnv args =
     let g = cenv.g
@@ -657,7 +665,11 @@ and TcPatLongIdentUnionCaseOrExnCase warnOnUpper cenv env ad vFlags patEnv ty (m
             let result = Array.zeroCreate numArgTys
             let extraPatterns = List ()
 
-            for id, _, pat in pairs do
+            for NamePatPairField(fieldName = fieldLid; pat = pat) in pairs do
+                let id = 
+                    match fieldLid.LongIdent with
+                    | [id] -> id
+                    | lid -> snd (List.frontAndBack lid)
                 match argNames |> List.tryFindIndex (fun id2 -> id.idText = id2.Id.idText) with
                 | None ->
                     extraPatterns.Add pat

src/Compiler/Driver/GraphChecking/FileContentMapping.fs

@@ -622,20 +622,9 @@ let visitPat (p: SynPat) : FileContentEntry list =
             let continuations = List.map visit elementPats
             Continuation.concatenate continuations continuation
         | SynPat.Record(fieldPats, _) ->
-            let pats = List.map (fun (_, _, p) -> p) fieldPats
-
-            let lids =
-                [
-                    for (l, _), _, _ in fieldPats do
-                        yield! visitLongIdent l
-                ]
-
+            let pats = fieldPats |> List.map (fun f -> f.Pattern)
             let continuations = List.map visit pats
-
-            let finalContinuation nodes =
-                [ yield! List.concat nodes; yield! lids ] |> continuation
-
-            Continuation.sequence continuations finalContinuation
+            Continuation.concatenate continuations continuation
         | SynPat.Null _ -> continuation []
         | SynPat.OptionalVal _ -> continuation []
         | SynPat.IsInst(t, _) -> continuation (visitSynType t)
@@ -650,8 +639,8 @@ let visitSynArgPats (argPat: SynArgPats) =
     | SynArgPats.Pats args -> List.collect visitPat args
     | SynArgPats.NamePatPairs(pats = pats) ->
         [
-            for _, _, p in pats do
-                yield! visitPat p
+            for p in pats do
+                yield! visitPat p.Pattern
         ]
 
 let visitSynSimplePat (pat: SynSimplePat) =

src/Compiler/Service/ServiceParseTreeWalk.fs

@@ -772,15 +772,15 @@ module SyntaxTraversal =
                 | SynPat.Ands(ps, _)
                 | SynPat.Tuple(elementPats = ps)
                 | SynPat.ArrayOrList(_, ps, _) -> ps |> List.tryPick (traversePat path)
-                | SynPat.Record(fieldPats = fieldPats) -> fieldPats |> List.tryPick (fun (_, _, p) -> traversePat path p)
+                | SynPat.Record(fieldPats = fieldPats) -> fieldPats |> List.tryPick (fun x -> traversePat path x.Pattern)
                 | SynPat.Attrib(p, attributes, m) ->
                     match traversePat path p with
                     | None -> attributeApplicationDives path attributes |> pick m attributes
                     | x -> x
                 | SynPat.LongIdent(argPats = args) ->
                     match args with
                     | SynArgPats.Pats ps -> ps |> List.tryPick (traversePat path)
-                    | SynArgPats.NamePatPairs(pats = ps) -> ps |> List.map (fun (_, _, pat) -> pat) |> List.tryPick (traversePat path)
+                    | SynArgPats.NamePatPairs(pats = ps) -> ps |> List.tryPick (fun x -> traversePat path x.Pattern)
                 | SynPat.Typed(p, ty, _) ->
                     match traversePat path p with
                     | None -> traverseSynType path ty

src/Compiler/Service/ServiceParsedInputOps.fs

@@ -613,7 +613,7 @@ module ParsedInput =
         let (|ConstructorPats|) pats =
             match pats with
             | SynArgPats.Pats ps -> ps
-            | SynArgPats.NamePatPairs(pats = xs) -> List.map (fun (_, _, pat) -> pat) xs
+            | SynArgPats.NamePatPairs(pats = xs) -> xs |> List.map _.Pattern
 
         let inline isPosInRange range = rangeContainsPos range pos
 
@@ -1120,6 +1120,8 @@ module ParsedInput =
         let last = List.last lid.LongIdent
         last.idRange.End
 
+    let lastIdentOfSynLongIdent (lid: SynLongIdent) = List.last lid.LongIdent
+
     let endOfClosingTokenOrLastIdent (mClosing: range option) (lid: SynLongIdent) =
         match mClosing with
         | Some m -> m.End
@@ -1293,18 +1295,24 @@ module ParsedInput =
             rangeContainsPos m pos
             ->
             pats
-            |> List.tryPick (fun (fieldId, _, pat) ->
-                if rangeContainsPos fieldId.idRange pos then
-                    let referencedFields = pats |> List.map (fun (id, _, _) -> id.idText)
+            |> List.tryPick (fun field ->
+                if rangeContainsPos field.FieldName.Range pos then
+                    let referencedFields =
+                        pats |> List.map (fun f -> (lastIdentOfSynLongIdent f.FieldName).idText)
+
                     Some(CompletionContext.Pattern(PatternContext.UnionCaseFieldIdentifier(referencedFields, caseId.Range)))
                 else
-                    let context = Some(PatternContext.NamedUnionCaseField(fieldId.idText, caseId.Range))
-                    TryGetCompletionContextInPattern suppressIdentifierCompletions pat context pos)
+                    let lastId = lastIdentOfSynLongIdent field.FieldName
+                    let context = Some(PatternContext.NamedUnionCaseField(lastId.idText, caseId.Range))
+
+                    TryGetCompletionContextInPattern suppressIdentifierCompletions field.Pattern context pos)
             |> Option.orElseWith (fun () ->
                 // Last resort - check for fun (Case (item1 = a; | )) ->
                 // That is, pos is after the last pair and still within parentheses
                 if rangeBeforePos mPairs pos then
-                    let referencedFields = pats |> List.map (fun (id, _, _) -> id.idText)
+                    let referencedFields =
+                        pats |> List.map (fun f -> (lastIdentOfSynLongIdent f.FieldName).idText)
+
                     Some(CompletionContext.Pattern(PatternContext.UnionCaseFieldIdentifier(referencedFields, caseId.Range)))
                 else
                     None)
@@ -1335,9 +1343,17 @@ module ParsedInput =
                 |> List.tryPick (fun pat -> TryGetCompletionContextInPattern false pat None pos)
         | SynPat.Record(fieldPats = pats; range = m) when rangeContainsPos m pos ->
             pats
-            |> List.tryPick (fun ((_, fieldId), _, pat) ->
-                if rangeContainsPos fieldId.idRange pos then
-                    let referencedFields = pats |> List.map (fun ((_, x), _, _) -> x.idText, x.idRange)
+            |> List.tryPick (fun f ->
+                let fieldId = f.FieldName
+                let pat = f.Pattern
+
+                if rangeContainsPos fieldId.Range pos then
+                    let referencedFields =
+                        pats
+                        |> List.map (fun f ->
+                            let lastId = lastIdentOfSynLongIdent f.FieldName
+                            lastId.idText, lastId.idRange)
+
                     Some(CompletionContext.Pattern(PatternContext.RecordFieldIdentifier referencedFields))
                 elif rangeContainsPos pat.Range pos then
                     TryGetCompletionContextInPattern false pat None pos
@@ -1348,13 +1364,22 @@ module ParsedInput =
                 // That is, pos is after the last field and still within braces
                 if
                     pats
-                    |> List.forall (fun (_, mEquals, pat) ->
-                        match mEquals, pat with
+                    |> List.forall (fun f ->
+                        let mEqualsOpt =
+                            match f with
+                            | NamePatPairField(equalsRange = m) -> m
+
+                        match mEqualsOpt, f.Pattern with
                         | Some mEquals, SynPat.Wild mPat -> rangeBeforePos mEquals pos && mPat.StartColumn <> mPat.EndColumn
                         | Some mEquals, _ -> rangeBeforePos mEquals pos
                         | _ -> false)
                 then
-                    let referencedFields = pats |> List.map (fun ((_, x), _, _) -> x.idText, x.idRange)
+                    let referencedFields =
+                        pats
+                        |> List.map (fun f ->
+                            let lastId = lastIdentOfSynLongIdent f.FieldName
+                            lastId.idText, lastId.idRange)
+
                     Some(CompletionContext.Pattern(PatternContext.RecordFieldIdentifier referencedFields))
                 else
                     Some(CompletionContext.Pattern PatternContext.Other))
@@ -1870,7 +1895,7 @@ module ParsedInput =
     let (|ConstructorPats|) pats =
         match pats with
         | SynArgPats.Pats ps -> ps
-        | SynArgPats.NamePatPairs(pats = xs) -> List.map (fun (_, _, pat) -> pat) xs
+        | SynArgPats.NamePatPairs(pats = xs) -> xs |> List.map _.Pattern
 
     /// Returns all `Ident`s and `LongIdent`s found in an untyped AST.
     let getLongIdents (parsedInput: ParsedInput) : IDictionary<pos, LongIdent> =

src/Compiler/Service/ServiceXmlDocParser.fs

@@ -16,7 +16,7 @@ module XmlDocParsing =
     let (|ConstructorPats|) =
         function
         | SynArgPats.Pats ps -> ps
-        | SynArgPats.NamePatPairs(pats = xs) -> List.map (fun (_, _, pat) -> pat) xs
+        | SynArgPats.NamePatPairs(pats = xs) -> xs |> List.map _.Pattern
 
     let rec digNamesFrom pat =
         match pat with

src/Compiler/SyntaxTree/SyntaxTree.fs

@@ -920,16 +920,37 @@ type SynSimplePats =
         match x with
         | SynSimplePats.SimplePats(range = range) -> range
 
+[<NoEquality; NoComparison>]
+type NamePatPairField =
+    | NamePatPairField of
+        fieldName: SynLongIdent *
+        equalsRange: range option *
+        range: range *
+        pat: SynPat *
+        blockSeparator: BlockSeparator option
+
+    member this.FieldName =
+        match this with
+        | NamePatPairField(fieldName = n) -> n
+
+    member this.Range =
+        match this with
+        | NamePatPairField(range = m) -> m
+
+    member this.Pattern =
+        match this with
+        | NamePatPairField(pat = pat) -> pat
+
 [<RequireQualifiedAccess>]
 type SynArgPats =
     | Pats of pats: SynPat list
 
-    | NamePatPairs of pats: (Ident * range option * SynPat) list * range: range * trivia: SynArgPatsNamePatPairsTrivia
+    | NamePatPairs of pats: NamePatPairField list * range: range * trivia: SynArgPatsNamePatPairsTrivia
 
     member x.Patterns =
         match x with
         | Pats pats -> pats
-        | NamePatPairs(pats = pats) -> pats |> List.map (fun (_, _, pat) -> pat)
+        | NamePatPairs(pats = pats) -> pats |> List.map _.Pattern
 
 [<NoEquality; NoComparison; RequireQualifiedAccess>]
 type SynPat =
@@ -966,7 +987,7 @@ type SynPat =
 
     | ArrayOrList of isArray: bool * elementPats: SynPat list * range: range
 
-    | Record of fieldPats: ((LongIdent * Ident) * range option * SynPat) list * range: range
+    | Record of fieldPats: NamePatPairField list * range: range
 
     | Null of range: range
 

src/Compiler/SyntaxTree/SyntaxTree.fsi

@@ -1046,12 +1046,36 @@ type SynSimplePats =
 
     member Range: range
 
+/// Represents a single named argument pattern a pair of the form `name = pattern`.
+[<NoEquality; NoComparison>]
+type NamePatPairField =
+    | NamePatPairField of
+        /// The identifier of the named field/parameter.
+        fieldName: SynLongIdent *
+        /// The range of the equals sign in `name = pattern`, if present.
+        equalsRange: range option *
+        /// The overall range of this name–pattern pair. Starts with `fieldName`'s range and ends with `pat`s range.
+        range: range *
+        /// The pattern associated with the named field.
+        pat: SynPat *
+        /// The separator trivia that follows this pair (e.g., semicolon or block separator), if any.
+        blockSeparator: BlockSeparator option
+
+    /// Gets the identifier of the named field/parameter.
+    member FieldName: SynLongIdent
+
+    /// Gets the overall range of this name–pattern pair, if available.
+    member Range: range
+
+    /// Gets the pattern associated with the named field.
+    member Pattern: SynPat
+
 /// Represents a syntax tree for arguments patterns
 [<RequireQualifiedAccess>]
 type SynArgPats =
     | Pats of pats: SynPat list
 
-    | NamePatPairs of pats: (Ident * range option * SynPat) list * range: range * trivia: SynArgPatsNamePatPairsTrivia
+    | NamePatPairs of pats: NamePatPairField list * range: range * trivia: SynArgPatsNamePatPairsTrivia
 
     member Patterns: SynPat list
 
@@ -1105,7 +1129,7 @@ type SynPat =
     | ArrayOrList of isArray: bool * elementPats: SynPat list * range: range
 
     /// A record pattern
-    | Record of fieldPats: ((LongIdent * Ident) * range option * SynPat) list * range: range
+    | Record of fieldPats: NamePatPairField list * range: range
 
     /// The 'null' pattern
     | Null of range: range